Pipe lines carrying water, oil, or mineral slurries which run on the earth's surface through remote areas where there is scant protection available can easily be the target of vandalism. Under such conditions flanged pipe lines may be vandalized merely for the scrap or resale value of the bolts and nuts which join the flanges. Pipe lines having mechanical couplings joining the pipe elements are also potentially vulnerable to such predation due to the exposed threaded fasteners used to assemble the mechanical couplings. For large diameter pipe lines the fasteners alone can provide what is regarded as significant scrap or resale value under such circumstances.
Removal of the fasteners holding the segments of a pipe line together can cause economic disruption until the pipe line is repaired and made operational. There is clearly a need for mechanical couplings which are resistant to tampering to help avoid or mitigate this potential problem.